The Role of the FLOWERING LOCUS K (FLK) gene in Regulating Defense and Development

FLOWERING LOCUS K (FLK) 基因在调节防御和发育中的作用

• 批准号: 2223886
• 负责人: Hua Lu
• 金额: $ 75万
• 依托单位: University of Maryland Baltimore County
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2223886&HistoricalAwards=false
• 关键词: Role; FLOWERING; LOCUS; FLK; gene

Plants are constantly challenged by pathogens and pests. Although being sessile, plants have evolved sophisticated mechanisms to recognize the invaders and activate defense responses. However, defense is an energetically costly process; defense activation can come at the expense of plant development. Flowering is one of the most critical developmental landmarks in the lifecycle of plants. Prior studies showed that plant defense and flowering time control are connected. However, the molecular basis underlying this connection has not been well understood. From a large-scale mutant screen in the model plant Arabidopsis that aimed to uncover novel defense genes, we identified a new mutant of a flowering time regulatory gene called FLOWERING LOCUS K (FLK) and our additional data support a defense role of FLK. This project will investigate the dual role of FLK in defense and flowering control. Knowledge obtained from this study shall shed light on how plants coordinate growth, development, and responses to pathogens. Without such knowledge, our design of strategies in improving the health and yield of crop plants will be limited. Furthermore, this project will provide a platform for the PI to engage students of diverse backgrounds in research training, including a postdoc, a graduate student, and undergraduates, K-12 teachers and high school students from underrepresented minority groups. Plant defense is a complex process that should be maintained in an intricate balance with development. Increasing evidence indicates the importance of post-transcriptional regulation of plant defense and development by RNA binding proteins. The K homology (KH) repeat is an ancient RNA binding motif found in proteins from diverse organisms. The role of KH domain proteins in pathogen resistance has not been well known. From a genetic screen for novel defense genes in Arabidopsis, a new allele of the canonical flowering gene FLOWERING LOCUS K (FLK) was identified and was associated with pathogen defense and late flowering. FLK encodes a triple KH-repeat protein. Data from the PI’s laboratory suggest for the first time that FLK is a multifunctional gene regulating transcript levels and/or alternative splicing of target genes. However, the detailed mechanisms of action of FLK, in particular in defense control, remain to be elucidated. The overall goal of this research is to uncover the molecular basis underlying how FLK and its pathway genes regulate plant defense and development. The PI will investigate structure-function of the FLK protein, identify and characterize FLK target genes, and characterize FLK interacting proteins in defense and development. Some FLK target genes could uncouple FLK multifunctionality at the molecular level. FLK and FLK pathway genes, especially those that uncouple multifunctionality of FLK, are potentially powerful molecular tools for developing novel biotechnological strategies to precisely control crop traits. Genome editing could be utilized to modify these genes to improve crop plants with better disease resistance against their natural pathogens while minimizing negative impacts on plant development. Information regarding FLK function, its interactors, and target genes will also provide insights to the study of KH domain proteins in other organisms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

病原体和害虫不断挑战植物。尽管是无柄，但植物已经发展出复杂的机制，以识别入侵者并激活防御反应。但是，国防是一个实质上昂贵的过程。国防激活可以以牺牲植物开发为代价。开花是植物生命周期中最关键的发育地标之一。先前的研究表明，植物防御和开花时间控制已连接。但是，这种联系的分子基础尚未得到充分理解。从旨在揭示新的防御基因的模型植物拟南芥中的大型突变体筛查中，我们确定了一个新的开花时间调节基因的突变体，称为开花基因座（FLK），我们的其他数据支持FLK的防御作用。该项目将研究FLK在防御和开花控制中的双重作用。从这项研究中获得的知识应阐明植物如何协调生长，发育和对病原体的反应。没有这样的知识，我们在改善作物植物健康和产量的策略的设计将受到限制。此外，该项目将为PI提供一个平台，以吸引潜水员背景的学生进行研究培训，包括博士后，研究生和本科生，K-12教师和来自代表性不足的少数群体的高中生。植物防御是一个复杂的过程，应保持与发展的复杂平衡。越来越多的证据表明，通过RNA结合蛋白对植物防御和发育的转录后调节的重要性。 K同源性（KH）重复是在来自不同生物体的蛋白质中发现的古老RNA结合基序。 KH结构蛋白在病原体抗性中的作用尚不清楚。从拟南芥中新型防御基因的遗传筛选中，确定了规范开花基因开花基因座（FLK）的新等位基因，并与病原体防御和晚期开花有关。 FLK编码三重KH重复蛋白。 PI实验室的数据首次表明FLK是靶基因的多功能基因调节转录水平和/或替代剪接。但是，尤其是在国防控制中，FLK的详细作用机理仍有待阐明。这项研究的总体目标是揭示FLK及其途径基因如何调节植物防御和发育的基础分子基础。 PI将研究FLK蛋白的结构功能，识别和表征FLK靶基因，并在防御和发育中表征FLK相互作用的蛋白质。一些FLK靶基因可以在分子水平上取消FLK多功能性。 FLK和FLK途径基因，尤其是那些脱离FLK的多功能性的基因，是潜在的强大分子工具，用于开发新型的生物技术策略来精确控制作物特征。可以利用基因组编辑来修饰这些基因，以改善对疾病的自然病原体抗病性更好的作物植物，同时最大程度地减少对植物发育的负面影响。有关FLK功能，其相互作用者和靶基因的信息还将为研究其他生物体中KH结构蛋白的研究提供见解。该奖项反映了NSF的法定任务，并通过使用该基金会的智力优点和更广泛的影响来审查标准，通过评估来诚实地支持支持。